Tradespersons working at construction sites regularly use portable radios for entertainment and to obtain weather reports. However, these radios lack certain features that would be desirable for such use. Small radios often lack the power desirable for overcoming ambient noise of other workers or to carry the sound over long distances outdoors. Although "boom boxes" may have the desired power output, they lack the ruggedness and splash proofing that is desirable. Other features, such as the convenient use of rechargeable batteries, are missing as well.
The prior art relates to some of these shortcomings. U.S. Pat. No. 4,006,764 of Yamamoto et al. relates to a protection case that can be used to enclose a tape recorder or radio to protect it from water spray or dust without seriously impeding sound transmission. U.S. Pat. No. 4,709,201 of Schaefer et al. discloses a modular battery pack with an on/off switch and contacts arranged for various modes of operation. U.S. Pat. No. 4,225,970 of Jaramillo et al. relates to a splash proof portable two-way data terminal/radio. It describes the use of tongue-in-groove elastomeric gaskets in the housing assembly as well as air-permeable water resistant material to achieve its results.
Other prior art include U.S. Pat. No. 5,572,592 of Muckelrath, which describes a field remote control radio transmitter/receiver which includes a weather resistant enclosure. U.S. Pat. No. 5,164,830 of Kim discloses a radio receiver which integrates a weather channel therein. U.S. Pat. No. 5,091,732 of Mileski and U.S. Pat. No. 4,761,813 of Gammel describe field oriented military radio systems. U.S. Pat. No. 4,961,994 of Cariou describes a waterproof coating material.
Shock-mounts for mounting delicate objects are described in U.S. Pat. Nos. 4,395,619 and 4,395,619, both of Harigai and U.S. Pat. No. 4,586,115 of Zimmerman. Retractable electric cords are disclosed in U.S. Pat. No. 3,984,645 of Kresch. Moreover, portable radios are described in general in U.S. Pat. No. 4,913,318 of Forrester.